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.NET Core C# Requires Chilkat v11.7.0+

Audit a PDF First, Optimize Only If It Is Worth It

See more PDF Optimization Examples

Demonstrates deciding whether to rewrite a PDF at all. "audit" costs a fraction of a second and changes nothing, so a batch job can audit every file and optimize only those where enough would be saved. Here the threshold is a tenth of the file; a file already as small as it can be is left alone.

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.NET Core C#
bool success = false;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  The PDF used in this example is available at watersense_accomplishments.pdf

Chilkat.Pdf pdf = new Chilkat.Pdf();
success = pdf.LoadFile("qa_data/pdf/watersense_accomplishments.pdf");
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

Chilkat.JsonObject json = new Chilkat.JsonObject();
Chilkat.JsonObject jsonOut = new Chilkat.JsonObject();
success = pdf.Optimize("audit",json,jsonOut);
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

int fileSize = jsonOut.IntOf("fileSize");
int estimated = jsonOut.IntOf("estimatedSavings.total");
Debug.WriteLine("fileSize:  " + Convert.ToString(fileSize));
Debug.WriteLine("estimated: " + Convert.ToString(estimated));

//  Only bother when at least a tenth of the file would go.
if (estimated > (fileSize / 10)) {
    Debug.WriteLine("Worth optimizing.");
    success = pdf.Optimize("optimize",json,jsonOut);
    if (success == false) {
        Debug.WriteLine(pdf.LastErrorText);
        return;
    }

    success = pdf.WriteFile("qa_output/watersense_optimized.pdf");
    if (success == false) {
        Debug.WriteLine(pdf.LastErrorText);
        return;
    }

    Debug.WriteLine("bytesSaved: " + Convert.ToString(jsonOut.IntOf("bytesSaved")));
}
else {
    Debug.WriteLine("Already small enough; left as it is.");
}